Special clinical considerations
Conception in serodiscordant couples
Women without HIV infection who have sexual partners with documented HIV infection are at risk of HIV acquisition during natural attempts to conceive (i.e. without a condom) if their HIV-positive partner has a detectable or variably detectable plasma viral load. Providers should discuss with their patients the
available information about the potential risks and benefits of PrEP in these circumstances (19). For women wanting to conceive where their HIV-positive male partner is stably virologically suppressed on combination antiretroviral therapy (cART), PrEP should still be offered to the woman if she expresses concerns about the risk of acquiring HIV in this setting.
Among women without HIV infection, the risk of acquiring HIV increases by approximately two-fold during pregnancy (20). In addition, if a woman acquires HIV infection during pregnancy there is a higher risk of HIV transmission to the infant than if the woman were to become pregnant during chronic HIV infection because the HIV viral load is much higher during acute HIV infection.
The current evidence suggests that PrEP can be used safely during pregnancy and breastfeeding (21).
The use of TD*-containing regimens by HIV positive women throughout pregnancy has not been associated with adverse pregnancy outcomes, but lowered BMD has been observed in newborns exposed to TD* in utero (22) as has a lower length and head circumference at 1 year of age (23).
In the Partners PrEP study, which compared the efficacy of tenofovir disoproxil fumarate / emtricitabine (TDF/FTC) versus TDF versus placebo to reduce HIV transmission in African heterosexual HIV-serodifferent couples, 431 pregnancies occurred; the average duration of in utero PrEP exposure was 5 weeks (24). There was no difference in the incidence of pregnancy, birth outcomes or infant growth in women who received TDF or TDF/FTC versus placebo PrEP (24). However, the authors noted that the confidence intervals for these findings were wide and therefore definitive statements about the safety of TDF/FTC as PrEP during pregnancy could not be made based on this study’s findings. A subsequent study from this group examined the pregnancy outcomes of 30 women who continued to use PrEP during pregnancy compared to 96 pregnancies without PrEP exposure. The authors found that there was no increase in adverse pregnancy outcomes, or restrictions in infant growth between the two groups (25).
The World Health Organization has included PrEP as an HIV prevention strategy during pregnancy (26) and a number of other jurisdictions recommend PrEP for safe conception and for use during pregnancy and breastfeeding (27).
Some women with HIV-positive partners may prefer to continue PrEP while pregnant, due to the increased risk of acquisition of HIV if their partners are not reliably virologically supressed during pregnancy, or due to high levels of anxiety (27).
Providers should discuss with their patients available information on potential adverse pregnancy outcomes when beginning or continuing PrEP during pregnancy so that they can make an informed decision. It should be noted that TD* is classified as category B3 by the Australian Therapeutic Goods Administration (TGA) (29), meaning that, to date, tenofovir has been taken by only a limited number of pregnant women and women of childbearing age, without an increase in the frequency of malformation or other direct or indirect harmful effects on the human foetus having been observed. However, studies in animals have shown evidence of an increased occurrence of foetal damage, the significance of which is considered uncertain in humans.
Therefore, the ASHM PrEP Guidelines Panel’s recommendation is that PrEP may be continued during pregnancy in women at risk for HIV acquisition, or who are unduly affected by anxiety about HIV acquisition.